This project focuses on the three coding regions of the Epstein-Barr virus (EBV) genome that are regularly transcribed in virally transformed, but virus non-producer cells. These regions have been designated as the LT-1, LT-2 and LT-3 regions. We intend to: i) Identify the gene products of these regions and map them to the recently sequenced EBV genome. ii) Purify the gene products and study their properties. iii) study the biological functions of the individual genes. For LT-1: Does this region code for an ACIF stainable nuclear antigen, identified as an 82K protein on Western blots? Is it responsible for the initiation of B-lymphocyte transformation, including polyclonal activation? For Lt-2: This region is already known to code for EBNA-1, the main nuclear antigen in EBV-transformed cells. Our recent success in producing EBNA-specific antibodies in rabbits by immunizing them with synthetic peptides deduced from the IR3 subregion of LT-2 is being exploited for the affinity purification of EBNA-1. For LT-3: Is this region coding for the EBV-specific antigen that we have recently detected by testing membrane fractions from EBV-transformed, virus non-producer cells in the leukocyte migration inhibition (LMI) test? Is this membrane antigen related to the EBV-induced membrane-antigen, LYDMA, the main target for immune surveillance? For all three regions: We wish to study the functional significance of each protein product separately, and in various combinations, by transfection experiments. They are carried out with mouse and rat fibroblasts, and also with human B-lymphocytes of normal or neoplastic origin. We are particularly encouraged in this endeavor by our recent success in transfecting lymphoid cells by using electroshock method.